Forex, CFD, and spread betting companies in the UK received twice as many complaints in the first half of 2026 as in the same period in 2025, according to data published by the Financial Conduct Authority (FCA). The total number of complaints across the financial sector received a total of 1.88 million opened complaints, which is an uptick of 6.3%. Investment Complaints are Growing Faster FCA registered nearly 68,000 investment product complaints in H1 2026, up 25.2% from H2 2025. In absolute terms, Investment (Individual Savings Account) remained the sector’s largest complaint category, with over 23,500 complaints received by the firms where such accounts are held. This is 28.7% more than in the previous reporting period. CFD and Forex firms received significantly fewer complaints over the same period, just 2,043, but the growth rate spiked to 53.5%. Investment platforms’ complaints increased by 45.6%, from 8,845 to 12,874.Complaint Volumes Vary across Retail Brokers Firm-level data provides another way to examine the figures. Among selected retail brokers and investment platforms, Trading 212 UK received the largest number of investment complaints during the period. However, its complaint rate relative to the number of accounts was 0.56 - the lowest in the group.At the same time, Interactive Brokers received fewer investment complaints, but reported 3.23 complaints per 1,000 investment accounts. This comparison shows why absolute volumes require context.This FCA contextual measure uses the number of relevant investment accounts reported by each firm at the end of its reporting period, regardless of their trading activity. The upheld rate shows the proportion of closed complaints that the firm accepted as fully or partly justified. It ranged from 2.3% at eToro and 6.7% at Trading 212 to 41.4% at Freetrade and 50.7% at IG Index. What is a Complain in FCA’s DefinitionFCA defines a complaint as an expression of dissatisfaction about a financial product or service provided by a regulated firm from retail customers, professional clients and other eligible complainants. The complaints are reported by the UK firm or its representative and used by the regulator in an aggregated form, with a firm-level breakdown available for those companies that had 500 or more complaints in a 6-month reporting period or 1,000 or more complaints in a year. This report reflects the state of the UK financial industry, highlighting areas that need attention and improvement to enhance customer experiences.This article was written by Tanya Chepkova at www.financemagnates.com.